Automatic generation of smooth paths bounded by polygonal chains

We consider the problem of planning smooth paths for a vehicle in a region bounded by polygonal chains. The paths are represented as B-spline functions. A path is found by solving an optimization problem using a cost function designed to care for both the smoothness of the path and the safety of the vehicle. Smoothness is defined as small magnitude of the derivative of curvature and safety is defined as the degree of centering of the path between the polygonal chains. The polygonal chains are preprocessed in order to remove excess parts and introduce safety margins for the vehicle. The method has been implemented for use with a standard solver and tests have been made on application data provided by the Swedish mining company LKAB.

Forest certification as an instrument for improved forest management within small-scale forestry

Since early 1990 ties, Swedish forest land is increasingly becoming certified. Today all major forest owners have joined the Swedish FSC-standard (Forest Stewardship Council), while small-scale forest owners preferably are joining the PEFC scheme (Programme for the Endorsement of Forest Certification). With the overall aim of gaining a better insight into which small-scale forest owners that have decided to take up on forest certification, and how their forest management practices have been affected by this choice, two set of data has been analyzed; one consisting Data Base of Forest Owner Analysis (DBFOA) data relating to approximately 14,000 properties whereof 1955 were found to be certified, and the other one including data from a follow up questionnaire sent out only to owners with certified forest properties. Results show that certified and non-certified forest properties are managed differently and in particular that harvesting on certified properties has increased. Differences in management seem to be connected principally to the fact that forest owners from generally more active sub-groups embrace forest certification requirements. Moreover, our results shows that economic motives for joining a certification scheme are just as prevalent as environmental motives and a majority of forest owners regard certification as something that favors profitability rather than consider it to restrict economic yield

Mercury toxicokinetics-dependency on strain and gender. Toxicology and Applied Pharmacology 243: 283–91

Mercury (Hg) exposure from dental amalgam fillings and thimerosal in vaccines is not a major health hazard, but adverse health effects cannot be ruled out in a small and more susceptible part of the exposed population. Individual differences in toxicokinetics may explain susceptibility to mercury. Inbred, H-2-congenic A.SW and B10.S mice and their F1-and F2-hybrids were given HgCl 2 with 2.0 mg Hg/L drinking water and traces of 203 Hg. Whole-body retention (WBR) was monitored until steady state after 5 weeks, when the organ Hg content was assessed. Despite similar Hg intake, A.SW males attained a 20-30% significantly higher WBR and 2-to 5-fold higher total renal Hg retention/concentration than A.SW females and B10.S mice. A selective renal Hg accumulation but of lower magnitude was seen also in B10.S males compared with females. Differences in WBR and organ Hg accumulation are therefore regulated by non-H-2 genes and gender. Lymph nodes lacked the strain-and gender-dependent Hg accumulation profile of kidney, liver and spleen. After 15 days without Hg A.SW mice showed a 4-fold higher WBR and liver Hg concentration, but 11-fold higher renal Hg concentration, showing the key role for the kidneys in explaining the slower Hg elimination in A.SW mice. The trait causing higher mercury accumulation was not dominantly inherited in the F1 hybrids. F2 mice showed a large inter-individual variation in Hg accumulation, showing that multiple genetic factors influence the Hg toxicokinetics in the mouse. The genetically heterogeneous human population may therefore show a large variation in mercury toxicokinetics

Activation of RAS Signalling is Associated with Altered Cell Adhesion in Phaeochromocytoma

Phaeochromocytomas and paragangliomas (PPGLs) are neuroendocrine catecholamine-producing tumours that may progress into inoperable metastatic disease. Treatment options for metastatic disease are limited, indicating a need for functional studies to identify pharmacologically targetable pathophysiological mechanisms, which require biologically relevant experimental models. Recently, a human progenitor phaeochromocytoma cell line named "hPheo1" was established, but its genotype has not been characterised. Performing exome sequencing analysis, we identified a KIF1B T827I mutation, and the oncogenic NRAS Q61K mutation. While KIF1B mutations are recurring somatic events in PPGLs, NRAS mutations have hitherto not been detected in PPGLs. Therefore, we aimed to assess its implications for the hPheo1 cell line, and possible relevance for the pathophysiology of PPGLs. We found that transient downregulation of NRAS in hPheo1 led to elevated expression of genes associated with cell adhesion, and enhanced adhesion to hPheo1 cells extracellular matrix. Analyses of previously published mRNA data from two independent PPGL patient cohorts (212 tissue samples) revealed a subcluster of PPGLs featuring hyperactivated RAS pathway-signalling and under-expression of cell adhesion-related gene expression programs. Thus, we conclude that NRAS activity in hPheo1 decreases adhesion to their own extracellular matrix and mirrors a transcriptomic RAS-signalling-related phenomenon in PPGLs.Funding Agencies|ALF Grants, Region Ostergotland [LIO-532021]; Medical Research Council of Southeast Sweden [FORSS-481781]; LiU Cancer, Linkoping University</p

Basic kinematics of the saddle and rider in high-level dressage horses trotting on a treadmill

REASONS FOR PERFORMING STUDY: A comprehensive kinematic description of rider and saddle movements is not yet present in the scientific literature. OBJECTIVE: To describe saddle and rider movements in a group of high-level dressage horses and riders. METHOD: Seven high-level dressage horses and riders were subjected to kinematic measurements while performing collected trot on a treadmill. For analysis a rigid body model for the saddle and core rider segments, projection angles of the rider's extremities and the neck and trunk of the horse, and distances between markers selected to indicate rider position were used. RESULTS: For a majority of the variables measured it was possible to describe a common pattern for the group. Rotations around the transverse axis (pitch) were generally biphasic for each diagonal. During the first half of stance the saddle rotated anti-clockwise and the rider's pelvis clockwise viewed from the right and the rider's lumbar back extended. During the later part of stance and the suspension phase reverse pitch rotations were observed. Rotations of the saddle and core rider segments around the longitudinal (roll) and vertical axes (yaw) changed direction only around time of contact of each diagonal. CONCLUSION: The saddles and riders of high-level dressage horses follow a common movement pattern at collected trot. The movements of the saddle and rider are clearly related to the movements of the horse and saddle movements also seem to be influenced by the rider. POTENTIAL RELEVANCE: Knowledge about rider and saddle movements can further our understanding of, and hence possibilities to prevent, orthopaedic injuries related to the exposure of the horse to a rider and saddle

Allele frequency spectrum of known ankylosing spondylitis associated variants in a Swedish population

Objective: The genetic predisposition to ankylosing spondylitis (AS) has been most widely studied in cohorts with European ancestry. However, within Europe, disease prevalence is higher in Sweden. Given this, we aimed to characterize known AS susceptibility variants in a homogeneous Swedish data set, assessing reproducibility and direction of effect. Method: The power to detect association within an existing Swedish targeted sequencing study (381 controls; 310 AS cases) was examined, and a set of published associations (n = 151) was intersected with available genotypes. Association to disease was calculated using logistic regression accounting for population structure, and HLA-B27 status was determined with direct polymerase chain reaction genotyping. Results: The cases were found to be 92.3% HLA-B27 positive, with the data set showing &amp;gt;= 80% predictive power to replicate associations, with odds ratios &amp;gt;= 1.6 over a range of allele frequencies (0.1-0.7). Thirty-four markers, representing 23 gene loci, were available for investigation. The replicated variants tagged MICA and IL23R loci (p &amp;lt; 1.47 x 10(-3)), with variable direction of effect noted for gene loci IL1R1 and MST1. Conclusion: The Swedish data set successfully replicated both major histocompatibility complex (MHC) and non-MHC loci, and revealed a different replication pattern compared to discovery data sets. This was possibly due to population demographics, including HLA-B27 frequency and measured comorbidities.Funding Agencies|Swedish Research Council, FORMASSwedish Research CouncilSwedish Research Council Formas [Dnr 2012-1531]; Wallenberg Scholar award</p